That's what I do. LOL Like you, we have about 8 months of heat.

I do all my errands early in the morning or after the sun goes down as it is cooler in the mornings and after the sun sets. However, as summer goes on it stays hotter in the evenings and the mornings vary more. I do take lots of cool showers during this time and that helps.

I keep some of the ice packs that come with my Copaxone and use them as needed when I am out and about. The sun is intense here so the car can heat up quickly to over 120 degrees in a matter of minutes. Using the ice while the a/c gets going in the car helps quite a bit. I also use a sun visor on my windshield to keep the blazing sun off the off the windshield. A cactus doesn't provide much shade. LOL

Here in the desert, we go from a/c to a/c.